The continuing improvement of society and economic booming have provided a good platform for further developing of the gasoline engine industry. The gasoline engine auxiliary industry developed rapidly because of the development of the gasoline engine industry. As one of the gasoline engine auxiliary industries the carburetor industry developed rapidly. Carburetor is an apparatus in a petrol engine which mixes fuel and air in order to make the petrol engine operate regularly. In the engine start-up process, reducing the amount of air by closing the intake passage, so that the density of mixture gas has increased and thus make the engine start. However, the existing carburetor has certain drawbacks. Before the existing carburetor leaves manufacturing, based on its technique which has marched with engine, to adjust the amount of petrol supplying of main oil installations and idle oil installations.
Therefore, when the carburetor supplies petrol to the engine, the proportion of the mixture of air and fuel reaches to the optimal and thus makes the engine work more efficient and saves energy. In order to improve the start-up possibility and reduce the times of start-up, it should remain in a high density of air-fuel mixture in the carburetor. After the start-up process finishes, when the carburetor works in a normal condition, it should reach the optimal condition in order to extend the working life and reduce air pollution. However, the existing carburetor cannot fulfill it.
The engine starting apparatus of the rotary valve carburetor which drives the cam interface connectors through the actuating lever and rotates the throttle lever, axially elevates the carburetor with a predetermined angle and axial distance, as disclosed in China Patent No. CN200610008981.X. The engine starting apparatus provided fuel-air mixture that is controllable and concentrated for the engine of starting up, but the carburetor in the said engine starting apparatus requires cam interface shifter, which drives the throttle lever to move in the axial direction. Such carburetor, which demands complex structural design, increases the axial dimension and hinders the application by itself.
CN 200520095240.0 disclosed a carburetor with low fuel consumption and low temperatures easy startup motorcycle carburetor. The thermostatic valve assembly is mounted on the cylinder of the motorcycle. The carburetor installed supplementary air holes parallel allocated with the air hole on the idling channel, and installed supplementary air holes parallel allocated with the air hole on the main channel based on the existing motorcycle. This carburetor improved the low temperature start-up performance of the engine to a certain degree. However, the internal structure and external structure of the carburetor are complex due to installed supplementary air holes parallel allocated with the air hole on the idling channel, and installed supplementary air holes parallel allocated with the air hole on the main channel based on the existing motorcycle, so that the cost of the design, manufacture and maintenance of the carburetor increased and thus the utilization of this carburetor is limited.
As the carburetor of the prior art cannot solve the said drawback, a carburetor which improves the ratio of fuel to air and keeps preferably fuel and air mixing ratio as to play a best performance of the engine and prolong engine life is urgently needed.